Conventionally, agricultural square balers are towed on a pair of wheels over a field for picking up hay, straw or silage grass and feeding such crop material to a baling chamber in which it is compressed to parallelepiped packages under action of a plunger which reciprocates inside the baling chamber. When the packages have reached a predetermined length a tying mechanism is operated to encircle the completed package with a plurality of strands to form a finished bale which will be ejected out of the baler.
As the outlet of the baling chamber is at a substantial height above the field and positioned at a certain angle, there is a risk that bales get damaged by their fall from the baling chamber. Bales are commonly damaged because their impact breaks some or all of the strands or because no proper bale drop is ensured, especially with short bales that are left standing on end when the bale is dropped. This problem is often solved by providing a guide or slide means at the exit of the baling chamber for reducing the height from which the bale is released onto the field and/or giving a wanted orientation to the bale. In the art such apparatus usually is referred to as a “bale chute” and examples can be found in WO96/29195 and EP-A-0771522.
EP-0974260, which is believed to represent the closest prior art to the present invention, discloses an agricultural baler having a bale chute which comprises a rear portion that is movable between an upper, bale sustaining, position and a lower, bale discharging, position.
In EP-0974260, the rear portion is pivotable about an axis located at its leading edge so that, as it pivots, its trailing edge is lowered closer to the ground to allow the formed bale to slide off the chute and to be lowered gently onto the ground. In this manner the rear portion can be lowered during the time interval of the actual discharge operation only. During the remainder of the baler operation, the rear portion is kept at a level sufficiently high for precluding collision with the ground.
It is desirable to weigh each bale as it is being discharged from the bale chute. There are various reasons to weigh the bales, such as enabling a farmer to assess the yield of a field and enabling a contractor to charge by the weight of the baled material rather than the number of bales. The density of the bales should also be monitored as it too may need to be controlled.